ios - iPhone NSMutableArray 和 NSKeyedUnarchiver unarchiveObjectWithFile 发布异常

Question

我将实现 .一旦我将它从文件加载到保留属性@property (nonatomic, retain) NSMutableArray *伙伴；对象的释放计数是 2(正确，它是 1of autorelease + 1 of retain of the property)但是没有人释放它并且保留计数变为 1，所以当我释放它时我得到-[__NSArrayM retainCount]: 发送到释放实例的消息(我认为因为 1 保留计数是自动释放)

完整代码如下:

BuddieListViewController.h

#import <UIKit/UIKit.h>
#import "Buddie.h"

@interface BuddieListViewController : UITableViewController {
    IBOutlet NSMutableArray *buddies;
    [...]
}
[...]
@property (nonatomic, retain) NSMutableArray *buddies;
[...]
@end

BuddieListViewController.m

#import "BuddieListViewController.h"
#import "Buddie.h"
#import "PreviewViewController.h"

@implementation BuddieListViewController

@synthesize buddies;
[...]
- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        [self loadFromDisk];
    }
    return self;
}

- (void)loadFromDisk {
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsPath = [paths objectAtIndex:0];
    NSString *appFile = [documentsPath stringByAppendingPathComponent:@"BuddieArchive.ark"];
    NSFileManager *fileManager = [NSFileManager defaultManager];
    if ([fileManager fileExistsAtPath:appFile]) {
        self.buddies = [NSKeyedUnarchiver unarchiveObjectWithFile:appFile];
        NSLog(@"1- buddies retain count %d (should be 2, 1 + 1autorelease)", [buddies retainCount]);
    } else {
        self.buddies = [NSMutableArray arrayWithCapacity:1];
    }
}
[...]
- (IBAction)cancelledBuddie:(NSNotification *)notification
{
    [editingBuddie release];
    NSLog(@"2- buddies retain count %d (should be 2, 1 + 1autorelease)", [buddies retainCount]);
    [buddies release]; 
    [self loadFromDisk];
    [self.tableView reloadData];
}

有人知道为什么会这样吗？

Answer 1

没有比这更好的了:

The number returned by retainCount is useless.

不要依赖它做任何事。使用 Instruments 中的 Leaks 工具来确定您是否正在泄漏对象。

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如果你崩溃了，很可能你遇到了僵尸。参见 this video了解如何使用 Instruments 寻找僵尸。